This invention relates to providing a positive shut off at the dispensing end of a plural chambered dispensing tube. There are several patented plural chambered tubes which can provide simultaneous dispensing of products from each chamber. All these designs can provide separation of the chamber contents except in one critical location, i.e., the dispensing end of the nozzle under the cap. In the dispensing region, the tube contents can mix during the filling process, in handling, and during and after dispensing. On certain applications, this area of mixing renders the separate chamber design almost useless. The design function of a plural chamber tube is incomplete without a closing function at the dispensing end.
The plural chamber tube designs that are currently state-of-the-art do not address this functional problem. All current designs utilize a simultaneous molding process to attach the tube body to the shoulder or dispensing end of the tube. There are several currently known methods wherein this can be accomplished, including injection molding and compression molding.
The object of this invention is to prevent mixing of multiple products being dispensed from a plural chambered tube prior to and after dispensation. The disclosure herein describes five embodiments that provide a seal and shut off of the product at the dispensing end of the tube to prevent cross-contamination of the plural chamber materials. The designs of these embodiments would be incorporated into the tooling of the tube manufacturing equipment. This invention when incorporated into current designs would have a negligible manufacturing cost increase over the current designs. It will enable an economical tube design to be used for many products which now require significantly more expensive packaging to function and maintain product integrity.